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Author Topic: Kapanadze Cousin - DALLY FREE ENERGY  (Read 11715599 times)

Black_Bird

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #810 on: November 18, 2012, 12:03:27 AM »
@itsu

Congratulations. Isn't 800V enough?

verpies

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #811 on: November 18, 2012, 12:40:01 AM »
despite some problems with noise and ringing in my nano-pulser circuit, even after re-arranging some parts, i managed to squeeze a 800V / 19nS pulse out of the 1n5408 dsr diode.

The MOSFET did get hot, but it was operating without a heatsink.
The good news is that your 1N5408 diode is showing some DSR effect.
The ringing is bad news - this is what makes your MOSFET hot and wastes energy and can produce excessive gate (>20V) and drain voltage (>250V) that will damage the MOSFET.

I don't have the result of measurement from Fig.20 but it is possible for the filters composed of L1+C1 as well as L2+C2, to ring.
If you take a look at the attached schematic it becomes apparent that L2+C2 form a series LC circuit, that will oscillate at its natural resonant frequency.

Indeed, this filter strongly attenuates:
1) Any voltage variations appearing at point +V2A acting as input and trying to get to point +V2B acting as output of the filter.
2) Any voltage variations appearing at point +V2B acting as input and trying to get to point +V2A acting as output of the filter.

However, this filter allows the point +V2B to move up and down in reference to the ground, at the frequency of LC resonance, which is  f = 1/( 6.28*(LC)0.5 ).  This calculates to 7.2kHz if L1= 220μH and C2=2.2μF.

So, are the values of L1 and C1 really 220μH and 2.2μF, respectively?
Note that the inductance of L1 can decrease to nH if its core becomes saturated (e.g. with too much current through its winding).

If "yes" then do you observe any ringing at 7.2kHz?
...or do you see the beat frequency of two LC tanks L1+C1 and L2+C2 (both oscillating close to 7.2kHz) ?

P.S.
The drain ringing frequency seems to be ≈90MHz after the rising edge and ≈30MHz after the falling edge of the signal on the gate of the MOSFET. This frequency is very far away from the resonant frequency of the power supply filter L2+C2 which would ring around 7.2kHz with 220μH and 2.2μF.  For comparison: 1nF and 3nH would ring at 92MHz.
Does the ringing frequency change at all when you short L2 or L1 or alter C2 or C1 ?
« Last Edit: November 18, 2012, 03:15:29 AM by verpies »

itsu

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #812 on: November 18, 2012, 09:22:05 AM »
The good news is that your 1N5408 diode is showing some DSR effect.

Right,  so wondering what the ordered Russian diodes will do.


Quote
So, are the values of L1 and C1 really 220μH and 2.2μF, respectively?
If "yes" then do you observe any ringing at 7.2kHz?
...or do you see the beat frequency of two LC tanks L1+C1 and L2+C2 (both oscillating close to 7.2kHz) ?

Yes, those are the value's as mentioned in the original Dally diagram.
I will try to find out the ringing frequency.


Quote
Does the ringing frequency change at all when you short L2 or L1 or alter C2 or C1 ?

I did short out both L1 and L2 one by one with a short (3 cm) wire. but nothing changed (was measuring gate and drain signals)

Regards Itsu

itsu

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #813 on: November 18, 2012, 09:56:21 AM »
@itsu

Congratulations. Isn't 800V enough?

Well,  probably, but i do not have the feeling this is the right pulse, as it is still fairly wide (20ns).
I expect to see a pulse in the 1-5ns range.

Regards Itsu

Black_Bird

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #814 on: November 18, 2012, 11:58:00 AM »
@itsu
It can be that your high voltage probe is widening the pulse. Anyway dv/dt seems to be the important parameter. What is the rise time of your pulse? (not the width)
In my experiments I had a bigger voltage by adding a second 1N5408 in parallel. Also, your output capacitor is 9nF, per your video. Try to reduce it.

mihai.isteniuc

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #815 on: November 18, 2012, 12:41:04 PM »

I did short out both L1 and L2 one by one with a short (3 cm) wire. but nothing changed (was measuring gate and drain signals)

A lot of atention should be gived to ringing filters. After I have connected L1 (from main Dally's coil) at the resonance of L2-C, the ring back it's so strong (at least in my case), that it's interfering with the pulses coming from VCO-NANOPULSER. The effect it's so strong that it's triggering the mosfet-driver and later the mosfet transistor even if I stop the VCO. The high voltage pulses are then generated with the frequency used for L1. I don't think this is OK  :)
 
Mihai

itsu

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #816 on: November 18, 2012, 12:59:21 PM »
@itsu
It can be that your high voltage probe is widening the pulse. Anyway dv/dt seems to be the important parameter. What is the rise time of your pulse? (not the width)
In my experiments I had a bigger voltage by adding a second 1N5408 in parallel. Also, your output capacitor is 9nF, per your video. Try to reduce it.

Hi Black_Bird, 

yes, could be that that HV probe interferes with the shape.
I am presently working on this ringing problem, so removed the DSRD, but will measure the rise time lateron.
Concerning the 9nF cap., i did this (moved from 1nF) because "exnihiloest" has some good results with a 10nF cap., see this forum thread:

http://www.overunityresearch.com/index.php?topic=1556.msg26574;topicseen#msg26574

But i can return to 1nF any second.

editted: i checked the HV probe specifications and it mentions a rise time of less then 7ns, so my 20ns probably are real.

Regards Itsu

Black_Bird

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #817 on: November 18, 2012, 02:27:13 PM »
Hi Black_Bird, 

yes, could be that that HV probe interferes with the shape.

editted: i checked the HV probe specifications and it mentions a rise time of less then 7ns, so my 20ns probably are real.

Regards Itsu
Actually the rise time of the probe will somewhat add to the real pulse rise time. In a rough calculation you can subtract 14 ns ( 7 ns rise time and 7 ns fall time). I would say your pulse is about 6 ns width.



slapper

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #818 on: November 18, 2012, 06:04:09 PM »
@itsu
It can be that your high voltage probe is widening the pulse. Anyway dv/dt seems to be the important parameter. What is the rise time of your pulse? (not the width)
In my experiments I had a bigger voltage by adding a second 1N5408 in parallel. Also, your output capacitor is 9nF, per your video. Try to reduce it.

did you try putting the diodes in series? i'm looking back at gotoluc's thread:
URGENT! WATER AS FUEL DISCOVERY FOR EVER

here is a post from that thread that, i think, gets pretty close to explaining what we are trying to achieve.
http://www.overunity.com/5024/urgent-water-as-fuel-discovery-for-everyone-to-share/msg116219/#msg116219

thanks.

nap

verpies

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #819 on: November 18, 2012, 06:42:49 PM »
If the gate signal stubbornly rings at 30MHz despite being grounded by the MOSFET Driver (pin 3 of U1) via the 4.7Ω resistor (R2), because the internal capacitance and inductance of the MOSFET are responsible for it (and cannot be eliminated), then this stubborn oscillation still can be selectively blocked by an LC tank circuit composed of C3 and L3 and inserted between pin 3 and gate of Q1, as shown below.

To block 30MHz the C3 could be 220pF and L3 could be 128nH (9x 3mm loops of 0,8mm wire in air).
..or any L and C combination that satisfies the equation 1/( 2*π*(L*C)0.5 ) = 30MHz

P.S.
According to this calculator, 9 turns of 0.8mm wire wound over a 3mm cylindrical former will form a 7mm long air-solenoid, that will have the inductance of 128nH.
« Last Edit: November 18, 2012, 08:02:06 PM by verpies »

Alfeen

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #820 on: November 19, 2012, 05:50:55 AM »
I received some parts today, and made a quick breadboard setup for this main generator too (4.6Khz) using the TL494.
Video to be seen here: http://www.youtube.com/watch?v=35OZREadOv0&feature=youtu.be
Regards Itsu

Hi Itsu ... and all,
I'm new to this forum, so let me briefly introduce myself. I'm a German engineer dealing mainly with electronics (including coils) during my job. Itsu, you actually recruited me for this forum (though unknowingly) because of the most commendable approach taken in your videos and the accurateness of your comments. Very good -- to say the least!

You had a question regarding the coax cable. Yes, BELDEN RG58A/U is really black PVC. But I could find the source from pictures 91684510.jpg through 91684518.jpg as posted by Edward_Lee. It was hard to read, but after a while I understood he really used *RG58U 50 Ohms (AUCAS Guangzhou Hscom Network Technology Co., Ltd.).jpg*, a white cable produced in China.

I'm still painstakingly working through your videos. A problem you had was explained in *Dally replication vco nano pulser*

I think Edward_Lee got the idea for his schematic(s) from *3985790_generator.pdf* page 3, an old (2003) document from a Siberian institute in the city of Tomsk written by A. Karaush, R.Potemin, S.Luyanov and O.Tolbanov. There you find the 7400 NAND gates to generate a rectangle and much of the rest of this stuff. You ended up with 220pF on Pin5 and a pulse width of about 100ns. To my understanding the desired overunity effect comes stronger when rise and fall times, as well as pulse duration itself goes down. But I may be wrong. At least the schematic says, rise time 1ns and peak 1kV. For the moment we are still far from that.

You said you had no success driving the mosfet with the two transistors. What type did you try? The schematic says KT972, which are Russian Darlington NPNs capable of 100MHz 60V 5A and having a current amplification of 750. A possible western replacement would be *BDW42G* which has power but can only do 4MHz, or *NTE48 50V 1A 1GHz*. State of the art, of course, are special mosfet drivers as you yourself already decided to use, like the MAX4420. Because we want rise times as low as possible it might help to try ixdd415 as a driver (3ns 15A) and IXFT30N50Q3 as the mosfet which can slew 50kV per µs @500V and 90 amps. But let us spare that for the moment to tweak efficiency in later experiments.

BTW, the three diodes later on in the schematic are specified in *3985790_generator.pdf* as VD1-VD3 - КД 522A (similar to our common 1N4148), having 50V 0,1A but a frequency of max 100kHz, which is a poor choice (or more probably intentionally misleading). These should be of the DSRD type, Russian ДДРВ.

I dare to question that your SCS106AG will lead to the desired sharp edges, because schottky is different from *Step Recovery*. Ask any anonymous alcoholic to get confirmation.

Ooops, little joke ;-) But, probably with some truth in it, because Step-Recovery Diodes are in a way much like alcoholics.

When their cathodes are connected to the negative voltage and a current flows, then they show almost no resistance and get drunk with electrons, so to speak. Thereby they become so saturated and thus oblivious to their environment (the voltage now slowly changing polarity)  that they keep drinking = the current flowing = conductive, even when after a while the voltage is fully reversed. Then the pub owner calls the police to get their bottle (the so-called intrinsic layer) emptied ... and all of a sudden they realize that their booze is all gone and switch off within picoseconds, faster than you can look. This gives us the desired sharp pulse. Normal scottish whisky drinkers -- excuse me, schottky diodes-- simply are not wired to behave like that. They instantaneously switch off as soon as their boss (or wife) appears at the pub's entrance door, meaning, as soon as their environmental tension (voltage) is reversed.

Finally, I try to understand what this coax cable is all about. I came accross an old publication from 1970 issued by one Genadin Mesyatz in Moscow. Chapters 1.1 through 1.4 explain the use of coax cables for creating high voltage nansosecond pulses.  Please find my rough translation of the preface below.

-----------------------------------
Preface
Interest in  generators of nanosecond impulses of high voltages quickly increases. In recent times they were used in quantum radio physics, in nuclear physics, in particle accelerators, X-ray analysis, in equipment for the high-speed photography etc. Extreme demand exists for the possibility of use of nanosecond generators for the decision such tasks in experimental physics, as creation of the powerful pulse lasers particle accelerators  and fast heating of plasmas.

Using high voltage nanosecond generators promises they are capable to provide huge amounts of energy (100J up to Megajoule) during short intervals in the range of 10 to 100ns and, thus, are power sources of enormous density. Already nowadays [published in 1970] impulse powers up to 10 Terawatt have become a reality.

Unfortunately, in the technical literature devoted to powerful pulse equipment, questions of formation of nanosecond impulses of a high voltage are poorly handled. This circumstance suggested the idea to the authors to impart their experience with the reader who is located in this area in the Soviet Union and abroad.

Considering the small volume of the book, we aspired to avoid bulky calculations, most to facilitate understanding of various ways of formation of nanosecond impulses and to define a technique to which the engineer should follow at a choice of the scheme and calculation of its components.

The first and second chapters are devoted to the main questions of formation of nanosecond impulses of a high voltage; the third and fourth chapters contain original helpful material in the theoretical basics, which is necessary for calculation and design of components for nanosecond generators. The final chapter is devoted to application of nanosecond impulses of high voltage. Authors gave main attention to those prospects who deal with application of powerful high voltage nanosecond impulses while quickly exploring the avenues of modern physics. ….

 
Introduction
The nanosecond pulse equipment is divided into equipment for medium impulses of a few hundred volts and below and to equipment for creation of high-voltage and powerful impulses of in the range of 10 000 — 10 million volts. The low-power nanosecond pulse equipment is helpful for experimental nuclear physics, the radio technician and computing equipment. The basic distinction between these two sections of pulse equipment is ruled by the character of used active elements. If in the first case such elements are tunnel diodes, fluorescent bulbs ‚ low-voltage high-speed thyratrons. In the second case various types of spark gaps, ferrites, high peak power hydrogen thyratrons, lines with electromagnetic shock waves etc.

Methods of generating low-power nanosecond impulses are quiet often mentioned in periodicals and text books. But how these powerful nanosecond impulses can be achieved is poorly covered in technical literature. As an excuse we hear that, on one hand, prior to the beginning of the 1950’s there wasn't great interest in such impulses, and on the other hand — great technical difficulties were encountered. The range of harmonics of nanosecond impulses extends up to the microwave band. Generation and transfer of such impulses therefore demands ultra wide band equipment. Moreover, how could transmissions of  such frequencies be obtained and maintained without undesired sparking, coronae and high voltage blackout. One parameter of strong influence is rendered by parasitic capacity and inductance of wires and other construction parts of the generator, which grow in size proportional to the size of the whole installation itself. Therefore requirements of shortening of the rise time and duration of impulses (especially when rectangular) became inevitable. But higher amplitudes need higher slew rates of --both-- voltage and current, while bigger physical dimensions lead to the growth of parasitic capacity and inductivity, slowing the whole thing down again. A vicious cycle, so to speak. *These contradictions can be resolved by application of coaxial designs*, solved with wisely tuned parameters and with the help of fast switching devices between the highly charged electrodes which shall have high electric durability.....
------------------------
So much for now.

itsu

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #821 on: November 19, 2012, 04:16:25 PM »
Hi Alfeen,

welcome aboard and thanks for the info on the RG58U (white afterall he) and the translated preface of that article.

But we came a long way since your mentioned video, so i guess you still have some reading up to do.

Regards Itsu

verpies

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #822 on: November 19, 2012, 05:31:59 PM »
Welcome to the forum Alfeen,

Do you have any experiences with MOSFET oscillations and parasitic inductances, that are beyond this paper ?

mihai.isteniuc

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #823 on: November 19, 2012, 07:24:00 PM »
Welcome Alfeen,
 
I'm happy to see you here.
 
Mihai

Alfeen

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Re: Kapanadze Cousin - DALLY FREE ENERGY
« Reply #824 on: November 19, 2012, 08:41:51 PM »
Welcome to the forum Alfeen,

Do you have any experiences with MOSFET oscillations and parasitic inductances, that are beyond this paper ?
Hi, verpies

Yes, I was recently doing a tesla coil @ ~4MHz, primary driven with a  mosfet against an adjustable 30V to 70V DC supply. When the mosfet gate was conducted at the wrong moment I had awful non-linear ringing instead of the desired smooth resonance. See pictures attached.

9 turns of 0.8mm wire wound over a 3mm cylindrical former will pick up every available magnetic noise and is likely to fail as a countermeasure for the 90MHz ringing of itsu. A shielded coil like "COILTRONICS - DR1030-151-R" might probably help for small mosfets with low input capacitance. But it can take only 680mA. When switching the gate on/off a high current is flowing to/from the gate which may saturate the ferrite, change the resonant frequency --> rendering the intended filter effect useless.

The solution in my case was --> to provide proper timing at the gate.

Regarding itsu's schematic: When the mosfet Q5 becomes conducting, a current starts to flow into coil W1. Proportional to its rising speed a voltage is induced in W2, which in turn causes a charging current through the two diodes (in series) so that the capacitor C34 1nF/1500V becomes fully charged. Because the diodes are both conducting there should be no more than 2.4V across the coax. Additionally the coax is shorted at its other end. So almost no voltage should be observed across the coax at low frequencies.

I maybe mistaken, but Diode D7 does not make much sense to me, neither as a DSR nor as a normal diode. It would just consume energy. If it is there with the intention of protecting the mosfet Q5 from overvoltage or negative voltage, it should rather be a schottky diode, Cathode to W1, anode to GND. Some mosfet types have one such diode already integrated. Pleas correct me if I'm wrong.

Ideally, the mosfet switch off happens at the same time when the current through W1 reaches equilibrium. In this moment we observe maximum flux in the transformer and maximum saturation of the core. Windings, core and the 1nF should be tuned to meet this requirement. To feed maximum energy from the transformer into the coax its impedance should match the 50 ohms of the coax. Given, a C34 = 1nF is used, then the secondary W2 should have 2.5 uH (measured with an almost saturated core) and the resulting resonant frequency would be 3.138MHz. Saturation can easily achieved with an adjustable DC fed into ten temporary additional windings on the core. The static current creates static magnetic flux. Any overlaid modulation from an inductance meter will show that at high current the inductivity goes down. When inductivity does not increase any more although you still increase the current then you have saturation. However this frequency 3.138MHz is not interesting here, as it will never go into the coax by design. It could be 1MHz or 20MHz as well. Only the impedance match counts.

If the mosfet is kept switched on after the current in W1 stopped rising, it heats up itself and the coil, wastes energy and creates all kinds of undesirable ringing -- coupling even back to the gate and to the 74HCT00 U2 & U3. So, my proposal is to start with a Dirac-like pulse at the output of the 74HCT00, say C17 = 3.3pF at Pin5. Then slowly increase this capacitor. Pulse repetition rate could be slowed down by replacing C14 = C15 = 1nF with bigger values, thus giving the mosfet more time to calm down in between the pulses. These capacitors can later be restored to 1nF (or even less) after the ringing issue is solved.

In an early video (I did not yet have the time to see all), itsu connected the mosfet with colored cables having clamps on each end. I guess this is not the case any more. But still, connecting wires between U2 & U3, driver and mosfet should be as short and thick as possible, especially the GND connection. Litz wire is preferred and a large copper area on the PCB for GND. Every millimeter counts at these frequencies.

After the ringing problem is solved let us look into efficiency. To increase the strength (energy content) of the back EMF pulse in the secondary --> the core should probably have a gap of 0,5mm up to 5mm. This is because considerable magnetic energy can only be stored in an air gap, not in the ferrite core itself. A ferrite is like a short circuit to the magnetic flux. With a closed core you have much magnetic "current" (measured in Tesla) but almost no magnetic voltage (measured in A/m). The resulting power is the product of both. Integrated over time we get the amount of energy. Something multiplied by almost zero remains almost zero. The air gap acts like a resistor in Mr. Ohm's circuit. Current goes down, but voltage rises. On the other extreme current becomes zero and voltage maximum. But again power is zero. Highest power (and thus optimum energy transmission) occurs, when impedance of voltage source and resistor match. A Dremel Rotary Tool (diamond blade and LOW speed works best) can create such gap in a ferrite (under rinsing water, use goggles to protect your eyes!). We will have to find out by trial and error which width works best.

When the mosfet is switched off, the field returns to the coil (forming a back EMF pulse) and current starts to discharge C34 1nF. If  1N5408 diodes are used, I expect them, to block the current flow within nanoseconds of the voltage reversal on the secondary output. If it has the alleged step recovery effect, the current will continue to flow for a while until all electrons stored between the p-layer and n-layer are exhausted. As there is no special SDR intrinsic zone in a 1N5408 this won't take too long. So the negative voltage will rise almost immediately, but not too quickly.

If instead a real SDR is used, after the voltage reversal (start of the back EMF)  there should still be no voltage across the coax cable. Only when the SDR switches off and the current flow is sharply interrupted then the desired pulse with a rise time of picoseconds should appear on the coax, causing standing waves therein. Those will decay over time. Stranded copper or solid copper does not make much of a difference. The standing waves  last longer if the cable used has smaller losses at high frequencies. To increase the reported 800V to over 1kV steal a winding from the primary or add one (or more) windings to the secondary to get a higher transformation factor. Instead of magnet wire copper band (167-9332 rs-online.com) and thick layers of  insulation (Kapton  436-2784 or  436-2778 @ rs-online.com) may be used to increase surface and reduce high frequency losses in the secondary W2. Also, for C34 a low inductance high impulse resistant type like WIMA FKP 1 is preferred.

kind regards